High-security phosphate-based electrolyte and lithium ion battery

The invention relates to a phosphate-based electrolyte and a lithium ion battery. The electrolyte is mainly characterized by taking at least one cyclic phosphate and at least one chain phosphate as solvent components. The advantages of the phosphate-based electrolyte are that: the two kinds of phosphates both have a flame retardation characteristic, and the cyclic phosphate can be subjected to ring-opening polymerisation under abuse conditions of high temperature, over charge or the like, and the electrolyte is gelated, the internal resistance of a battery increases, and therefore the battery security is improved. The cyclic phosphate can form into membranes on an anode surface and a cathode surface of the lithium ion battery, and improves the compatibility between the electrolyte, and the anode and the cathode; the usage of the chain phosphate helps to reduce the electrolyte viscosity and improve the electrolyte conductivity, and good multiplying power performance and low temperature performance are provided in the corresponding battery system. The security of the lithium ion battery can be improved substantially by using the electrolyte.